v2.4.0.6

Debt (Details Textual) (USD $)	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Commercial Paper Programs (Textual) [Abstract]
Total amount under revolving credit facilities	$ 7,500,000,000
Maturity period of commercial paper (in days)	P90D
Letters of credit issued	782,000,000
Commercial paper outstanding	1,008,000,000	1,055,000,000
Credit facilities remaining after commercial paper outstanding and issuance of letters of credit	6,500,000,000
Debt (Textual) [Abstract]
Classification of short-term debt as long-term debt	920,000,000
Revolving Credit Facilities [Member]
Commercial Paper Programs (Textual) [Abstract]
Direct outstanding borrowings under the revolving credit facilities	0	0
Letters of credit issued	0	0
ConocoPhillips [Member]
Commercial Paper Programs (Textual) [Abstract]
ConocoPhillips Commercial Paper Program	6,350,000,000
ConocoPhillips Qatar Funding Ltd. [Member]
Commercial Paper Programs (Textual) [Abstract]
ConocoPhillips Commercial Paper Program	1,150,000,000
7.625% Debentures Due 2013 [Member]
Extinguishment Of Debt Disclosures [Abstract]
Stated percentage of debt	7.625%
Original amount of debt instrument	100,000,000
5.50% Notes Due 2013 [Member]
Extinguishment Of Debt Disclosures [Abstract]
Stated percentage of debt	5.50%
Original amount of debt instrument	$ 750,000,000

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Commercial paper program.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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-Name Regulation S-X (SX)

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount borrowed under the credit facility as of the balance sheet date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.

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Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

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